Pages Menu

Column originally published Oct 9, 2001

Slapped-Cheek Disease Is Caused By Human Parvovirus B19

Question: I am a kindergarten teacher. On the first day of school, one of my students had very red cheeks. At first I thought someone slapped him. His mother told me later that he had an infection called “slapped cheek disease.” I have never heard of it, so I went on the Internet. I was very frightened when I read that it can be contagious; I am five-months pregnant. Can I get infected and pass the infection to my baby?


I hope this column comes quick enough for you to alleviate your worries. Slapped cheek disease is caused by a virus infection. It has been called Erythema Infectiosum and Fifth Disease by the medical profession. For many years, doctors didn’t know what caused the infection. By observing children contracting the disease from each other, it was speculated that a virus infection is the most likely cause of this illness.

This was finally confirmed about 15 to 20 years ago. The virus was officially named Human Parvovirus B19. Further research showed that the virus is present everywhere around the world. Most epidemics happen in late winter and early spring, in school settings where there are lots of children.

Human Parvovirus (HPV) is usually spread through respiratory secretions. Most children just develop mild cold-like symptoms. There can be low-grade fever, running nose, some aches and pains. About 15 to 30% of children will develop the typical intensely red rash on the face, giving the nickname “slapped cheek disease.”

Another rash can develop on the trunk, and then spread to the arms and legs. This second rash has a lace-like pattern, and can be slightly raised. It is often quite itchy. The rash can come and go, especially when exposed to heat or to the sun, and can last for weeks to months.

For most children, the infection is nothing more trouble than an embarrassing rash. Complications are extremely rare. Almost half of all children would have been infected with HPV by the time they reach 15 years of age. This also mean about half of all young adults are susceptible, and will get infected sometime during their adult life.

HPV infection can be a serious problem for those with haemolytic anaemia. The red blood cells in these individuals break down very easily due to a number of medical conditions. When they contract HPV, their bone marrow would stop producing red blood cells (and sometimes all types of blood cells), leading to a life-threatening condition.

Patients with weakened immune system (immunodeficiency) also develop more serious HPV infection. This is especially true in AIDS patients, their haemoglobin drops significantly when infected with this virus.

When healthy adults get infected with HPV, fortunately the illness is mostly very mild. They do not develop the rash that is so typical in children. There may be a few small red spots on the arms or legs. Painful and swollen joints happen frequently in women infected with HPV. However, these do not progress to long-standing arthritis.

If a pregnant woman contracts HPV, the virus can pass through the placenta and infect the foetus. Most of these infections are still very mild, and do not cause any kind of problem. Once in a while, however, complications can happen to the foetus. About 2 to 6% of foetus infected during the first half of pregnancy may die, resulting in miscarriage.

You have a very good question: can you pick up the virus from your student, is this going to harm your unborn baby? I will try to explain to you as carefully as possible.

A healthy child usually develops illness between 4 to 21 days after contracting HPV. The time this child will become infectious to others is just before the onset of illness. By the time the child develops the typical rash, the chance of him spreading the virus (and infecting you) is very low. Since your student already had the rash on the first day of school, you likely will not pick up HPV from him. However, many children in your kindergarten class are still susceptible, and may pick up this virus from their siblings and friends in the next few weeks to months, and spread the virus in the classroom.

As for yourself, there is a very good chance that you might have been infected with HPV during your childhood, while you were attending school. If you have had the typical rash, it would be hard for you to forget. However, the majority of children only develop cold-like symptoms. If you were never infected, and have no antibodies against HPV, you can potentially pick up the virus through one of your students during your teaching career.

The crucial question really is this: do you have immunity against HPV at this time. The only way to answer is through a blood test. Fortunately, blood tests have become available in the last few years, to determine whether a person has had a recent or past HPV infection. If blood test shows that you have a past infection (and immunity), you don’t have to worry about catching this virus at all.

On the other hand, if blood test shows that you have no immunity, then you are susceptible to HPV. However, do not become paranoid. Good handwashing can still reduce the chance of picking up this virus. If you do get infected in the next few months, your baby likely will be fine; the chance of serious infection in the second half of pregnancy is very low.

I hope the information that I provided here is useful to reduce some of your anxiety. You can also talk to your doctor about this concerns. Good luck with your pregnancy!